code: def _return_node(candidates) -> Optional[OptNode]:
      if not candidates:
          return None
      return OptNode(content={"name": choice(sorted(candidates))})
  
file_path: FEDOT/fedot/core/pipelines/pipeline_node_factory.py
imports: from random import choice
  from typing import Optional, List
  from golem.core.optimisers.graph import OptNode
  from golem.core.optimisers.opt_node_factory import OptNodeFactory
  from fedot.core.pipelines.pipeline_advisor import PipelineChangeAdvisor, check_for_specific_operations
  from fedot.core.pipelines.pipeline_composer_requirements import PipelineComposerRequirements
  from fedot.core.repository.pipeline_operation_repository import PipelineOperationRepository
  from fedot.utilities.custom_errors import MethodNotImplementError
label_desc: Use image node_id 6 for calling the PipelineOptNodeFactory obj's underlying member method code with example usage: obj._return_node(candidates) and returns: OptNode, None